With the agrotechnique of tillless, ridge and covering culture in arid farming field, the rice can become exempt from irrigation and yield well. Through this cultivation technique,a good soil structure can be formed and maitained. So that a great deal of natural precipitation can be efficiently conserved and utilized,which prevents loss of water and ero sion of soil. It is showed that this farming technique is available in irrigation of dry farmland and transformation of du alpurpose field,so as to save water,manure and labour.